Interpreting web.xml

Hi, I thought this is the close to right place to post this thread. Here I go..

I need to understand top-level element of deployment descriptor web.xml.
(I read that, namespaces are to avoid conflicts of element names. Fine. And the namespace value is just treated as string(even if it is a URI) by XML Parser. Fine?)
See the below.

While working with eclipse for Ctrl+Space it gives the possible elements and validates it.
Will it go to that URI every time or what is the deal here.

I really appreciate anybody explaining each element of the above code..

I am going to post a few links in answer to your question. Its not a direct answer, but then I think its a pretty though question, not many people (including me) really understand or care about what the top-level element of deployment descriptor are ...

To understand some basics you need to dive a bit deeper into XML name spaces and XSD,

The actual schema for the Servlet 2.5 spec is @ xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
hit the link in the browser and you should see the XSD (XML Schema)

Advice - If you new to programming leave those elements out as what is explained 'bunch of strings that you need to add to yu web-xml' ... as you grow and work with other stuff (XML, XQuery, Web-Services) you'll come to understand those thing in detail. As a web-developer going into the details is kinda of an over kill ....